Who do you add on facebook?

Do you allow anyone that ask you to be their friend to be your friend on facebook? Me I only allow those that I know personally. I don't want others that I don't know seeing photos of me and my family. I feel that is just odd and creepy.

I have about thirty 'friends' on Facebook, all of whom I know in real life or online in some way or another. I don't just add randoms on Facebook or allow others to add me randomly. The very few times that I have added a casual acquaintance in the past, it led to some unfortunate consequences. I've considered starting another Facebook account just to add 'casual acquaintances', such as people who are into Farmville 2, so that we can send each other gifts. But, then I would have to start my Farmville 2 game over. :/

Erh, I only allow/add people that I know in real life. I'm not accepting strangers or so.

I've used Facebook for many years and back in the days I've added a bunch of people that I don't know. I've found them through different apps. Nowadays I add only people I know.